Improvement in the manufacture of ziuo



A. G. .HUNTER, or FLINT, Wr tes,

Letters Patent No. 77,618, elated May 5, 1868,

IMPROVEMENT IN THE MANUFAOTUBE or ZINC.

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TO ALL WHOM IT/MAY eouonmw:

Be it known that I, A. G. HUNTER, of Flint, Wales, temporarily residing in Fair Haven, in the county of.

New Haven, and State of Connecticut, have invented a new Improvement in the Manufacture of Zinc; and I do hereby declare the following to be a-full, clear, and exact description of the same.

In the ordinary'proccss o'f smelting zinc, the ore, after suitable preliminary treatment, is intimately mixed with carbonaceous matter, the mixtur'e'then placed in retorts or crucibles, and the zinc distilled off by a high heat. Great expense and'loss are incurred by the'use of such retorts or crueibles, and my improvement relates to a process whereby their use is dispensed with.

I In order to the clear understanding of my improvement, I will proceed to a full description of the same.

I take the zinc ores, after having been subjected to the usual preliminary treatment, and intimately mix them with the usual quantity'of carbonaceous matter, and place this mixture on'the hearth-of.areverberatory furnace, in which it is aetedon directly by the heat and flame from the fire; In order to effect the reduction of the zinc from its ore, care must be taken to prevent the presence of any free oxygen in'the flame, or heated gasespassing over the zinc-ore mixture. This may be accomplished either by keeping a thick mass oi burning fuel in the fireplace, or by introducing carbonic oxide, carburets of hydrogen, or hydrogen gas, or other deoxidizing agent, at the fire-bridge, so as to be mixed with the flame' from the fir'e before it reaches the zinc-ore mixture, care being taken to prevent the admission of air at any other part of the furnace except through the grate-bars of the fireplace, which must be well filled with fuel while the zinc-ore mixture is under treatment. By the reducing-action of the heated gases and flame, and of the carbonaceous matter mixed with the ore, the zinc' the ore contains is liberated in a metallic state, and distills oil as a vapor, mixedwith the hat-ed gases and flame from the fire. I condense the zinc vapor to metal by causing the heated gases, flame, and zinc vapor, previous to their reaching the chimney, to. pass through a pipe or condenser surrounded with water, which cools the gases sufliciently to allow the zinc to. deposit ina metallic state. I provide, in this pipeorcondenser, suitable rece'sses or cess-pools, to receive the melted zinc nsdeposited, from which it may be run off into moulds; also suitable openings, through which the pipe may be cleaned out. Either a stationary or a revolving, reverberatory furnace may he used to heat the zinc ores in, and the condensenmay be either vertical'or horizontal, or both alternately, and the sizes of the furnace and condenser maybe varied, to suit the amount of' work required to be done. I have found'a furnace-hearth eight feet square, and a condenser twenty inches diameter and sixty feet long, a convenient size; but these proportions may be varied.

Having thus fully described my invention, what I claim as new and useful, and desire to secure by Letters Patent, is- 1 The process of extracting zinc from its ores by the direct application of heat to the saidores, without the use of'crucibles or retorts, tocontain the said ores, the heated gases and flame being, previously to their contact with the zinc, carefully deprived of free oxygen, and the subsequent condensation of the zinc vapor to the metallic state, all'substantiall'y as herein described. I

- A. G; HUNTER.

Witnesses: I)

l A. JKTIBBITS, I

J. H. SHUMWAY. 

